Internal combustion engine



A ril 21, 1936. c, GOODE A 2,037,778

INTERNAL COMBUST ION ENGINE Filed Sept. 25, 1933 0 ILBERT a /JARENOE W MILLER GEORGE E. m/rm/vaTo/v.

%7 ATTORNEYS.

Patented Apr. 21, .1936

A E T orFlCE :INTERNAL conv nes ENGINE Gilbert C. Goode, Birmingham, and Clarence W.

Miller and George R. Harrington, Detroit,

Mich., assignors to Chrysler Corporation, De-- I troit, Mich., a corporation of Delaware Application September 25,1933, Serial no. 690,800

.z'cl'aims. (01423-32): a

on the'piston and not into: the compression This invention relates to internal combustionengines and more especially to the type inwhich. a restricted passage or throat is provided between of intake. and exhaust valve, compression chamber and 'fuel injection ,nozzle, such that large 5 thecompression chamber and the working per-- '5 tion of the'cylinder, and in which the fuel is inJ'ec tures. a

The main object ofthe invention is to improve. the combustion in engines of this'type.

Another object is to cause the injected fuel and air to' flow in the same direction into the compression chamber. T

Another object is to improve the mixture of air and fuel. I l5 Another object is to reduce opposition to the discharge of fuel through the compression I I I inder head and a portion of the cylinder block of chamber. I I

Another object. is to cause, on the return stroke of the piston of the engine, a high concentration of air in the compression chamber to be mixed with a high concentration of fuel at a point adiacent the throat joining the'compression chamher and working portion of the cylinder.

* Another object is to spray the fuel directly on the exhaust valve. I

Another object is to arrange an exhaust valve so that it provides a wall of the compression chamber and reduces the flow of heat therefrom.

Another object is to avoid cooling the fuel due to projecting the same against cool walls,

I Another object is to provide a compression. chamber which conforms in shape closely to the fuel spray cone pattern.

A further object is toprovide for a long spra cone in the compression chamber of a small bore engine. I I

Another object is to cause ,the last particles of I fuel discharged from the injection nozzle to be exposed to ample amounts of air to givecomplete burning.

Another object is to causethe mixture of fuel and air to sweep past the discharge end of. the injection nozzle as combustion takes place and while the fuel is being discharged.

I Another object is toprovide for the burning of thellghter end of oil fuel before top dead center of the piston, by causing these. ends to be first thrown against the exhaust valve and ignited by heat stored in that valve so that the resulting pressure increase fumishes the additional heat necessary for rapid combustion of all the fuel andreverses the direction of air flow.

A still further object is to provide an arrangement wherebyfuellost from the fuel spray drips ted into air athi'gh pressures and tempera- [by the Iine 22 of Fig. 1';

chamberL I Another object is to. provide an arrangement intake and exhaust valves may be employed,

whereby ample amounts of air are provided for high'speed operation and complete scavenging of I the compression chamber is obtained.

' Other objects and advantages will-become ap 10 parent from the following description and appended claims.

For, the, purpose of illustrating the genus of the invention, atypical concrete embodiment is shown in the accompanying drawing, in which: 15

Figure 1 is a, transverse section through a cylan internal" combustion engine, constructed. in

acccordance with the principles of this invention; I

I Fig.2 is a bottom plan-.01 a portion of the 20 cylinder head, the view being taken as indicated Figs. 3, 4 and .5 are sections taken on the line 3-.- and 5-5 of Fig.1.

Referring to the drawing, 10' designates the 5 cylinder block of an internal combustion engine having a cylinder ll -infwhich is disposed. a piston l2, illustrated at approidmatelytop dead center position. While the drawing illustrates.

but one cylinder, it is to be imderstood that our 30 invention is applicable toengines including any desired number ofcylin'ders.

exhaust passage I3 is provided in a lateral extension ll of the cylinder block l0 and an-exhaustv valve l5 is arranged to move onxa line 35 parallel. with the axis of the cylinder II to, open or close the port It of, the-exhaust passage I 3.

A cylinder head 11 covers the cylinder block l0 and isnconstructed so asto, provide passages I 9 for a cooling fluid and a combustion chamber 20 .40 above the cylinder, and extending fromthe longitudinal center. line of the engine, designated 2|, across-the headto include the exhaust valve. l5. As illustrated in Figs. 1,' 2, and 3, the portion or the compression chamber!!! disposed above, the 45 cylinder ;II is of comparatively small volume 'constituting arestrictedpassage'or throat between the compression chamber 20 and the working portion of thecylinder' H.- The lobe portion. 23 of the combustion chamber 20 extends overthe '50 whole of the tenor the 'exhaustvalve I 5 and constitutes the major portion ofthe compression above the exhaust valve. Otherwise the compression chamber 20 is located either aft or forward of the transverse centerline of the engine, designated 24, and in substantially tangentail relationship with respect to the cylinder bore. This arrangement is provided to promote radial air swirl and to allow sumcient room for the air intake valve 25 located directly above the piston l2. Since the compression chamber 20 is located across the cylinder head I1, it is restricted in length, only by the width of the engine including the lateral extension H, and consequently the compression chamber can be made comparatively long, thus permitting the employment of a long spray cone. The use of a long spray cone provides for a large area of contact between the injected fuel and air, and a more thorough breaking up of the injected fuel. The location of the exhaust valve I5 so as to constitute one of the walls of the compression chamber 20 and of-the air intake valve 25 directly above the piston offers no restriction relative to the size of these valves so that a comparatively large intake valve 25 may be employed to assure ample air required in high speed performanceof the engine, and a comparatively large exhaust valve may be employed to insure complete and direct scavenging of the compression chamber. The present engine depends upon heat for effecting rapid combustion of the mixture of fuel and air. This heat may be obtained entirely by compression or by utilizing a combination of the residual heat of combustion and the heat of compression. The use of the heat of compression alone involves serious diihculties because in small bore engines the ratio of the water cooled surfaces to the volume displaced by the piston is such that the heat loss is great, thus requiring an excessive compression pressure to maintain a suitable temperature for rapid combustion. The present engine utilizes a combination of the residual heat of the combustion chamber or parts thereof and the heat of compression of the mixture of fuel and air. In the present instance the entire mixture is concentrated in the compression chamber directly over the exhaust valve l5 and contacts the chamber walls of which the exhaust valve forms one side. The exhaust valve 15 is heated by the exhaust gases passing by the same so that it becomes a hot-spot in the compression chamber, and its heat is utilized for the purpose of intensifying the heat of compression,

In the development of the compression chamber 20, this chamber increases in cross-sectional area from the centerline 2| of the engine to the center of the exhaust valve where the'area becomes maximu'mand the wall of the compression chamber opposite the piston I2 is of dome shape with its curvature gradually decreasing or flattening out from the longitudinal centerline of the engine to approximately the center of the exhaust valve I 5. Thus the compression chamber, in shape, conforms closely to that of the spray cone pattern of the fuel injected into the compression chamber. The proper location of the fuel injection nozzle is essential, since upon its correct placement depends the successful accomplishment of results in accordance with the principles involved in the design of the compression chamber.

The fuel injection nozzle 30 is located at the inside end of the compression chamber directly above the piston and in a position such that its spray cone is concentric with the chamber development. The injection nozzle 3 0 is arranged at takes place. 4 nozzle 30 directly over the cylinder and with the a slight angle of inclination with respect to the face of the cylinder block so as to direct the injected fuel toward the hot exhaust valve I5. A separate conduit 3| may be provided to supply cooling fluid for the discharge end of the nozzle 30 from any desired source. Fuel injection begins just prior to the arrival of piston I! at top dead center, ,at which time the air of compression is flowing from the piston, to the lobe portion 23 of the compression chamber disposed above the exhaust valve 15, the air flowing with considerable turbulence and being restricted to travel in a direct line with the spray cone. The air and fuel traveling in the same direction over a comparatively long route and with a large area of contact, promotes a very thorough process of mixture. The lighter ends of the fuel and air naturally arrive at the exhaust valve first where they are immediately ignited by the heat stored in the exhaust valve which causes an increase in pressure and furnishes the additional heat necessary for rapid combustion andreverse flow of the air and fuel mixture.

The dome-shaped wall 26 of the compression chamber 20 terminates in a slight shoulder 21 at a point approximately above the center of the exhaust valve i5 to cause added turbulence of the air entering the lobe portion 23 of the compression chamber and'to' aid in directing the lighter ends of the injected fuel against the heated exhaust valve. A glow plug 28 of high electrical resistance may project into the compression chamber 20 for starting purposes. The glow plug may be heated from any suitable source of electrical energy.

The reversal of the direction of air flow causes added turbulence and the air moves in radial swirls due to the relative arrangement of the cylinder wall 18 and the compression chamber 20. As fuel is being injected during thisperiod. a very complete mixture is formed and rapid combustion The location of the fuel injection discharge end of the nozzle opening into the small end of the compression chamber 20 causes the last drop of fuel injected into the cylinder to be exposed to ample air to give complete burning. During compression and. while the fuel is being discharged across the piston toward the exhaust valve, the residual heat in the piston is transferred to the fuel. Since the lighter ends of the fuel are first thrown against'the heated exhaust valve, combustion is initiated just prior to top dead center causing an increase in pressure and a rise in temperature which initiates the burning of the heavier end which sweeps back across the compression chamber cleaning the last drops of fuel from the discharge nozzle and thoroughly mixing these last drops with air to insure complete buming of the mixture. It is also noted that in the present arrangementany fuel lost from the spray drips upon the piston rather than remaining in the compression chamber. At the initiation of the discharge of fuel into the compression chamber the fuel and air flow in the same direction thus reducing opposition to'the discharge of the fuel into the compression chamber. The arrangement of the exhaust valve as a'wallof the combustion chamber reduces the flow of heat from the combustion chamber and thus reduces heat losses of the engine. In injecting the fuel into the compression chamber the fuel is not projected against cool walls so that complete and rapid burning of the fuel is insured.

As many changes couldbe made in the above construction and many apparently different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. In an internal combustion engine, a cylinder block provided with an exhaust valve and a cylinder bore, the main portion of said exhaust valve being offset longitudinally of said cylinder block in one direction from the transverse center line of said cylinder bore, a cylinder head having an inlet valve, the main portion of said inlet valve being oifset longitudinally of said head in an opposite direction from said center line of said cylinder bore, a compression chamber in said cylinder head having a main body portion registering with said exhaust valve and a communicating substantially narrow channel portion extending over said cylinder bore and overlapping the projection of said intake valve in a plane parallel to the plane of the head end of said block, said channel varying in curvature from a minimum radius of curvature at the cylinder end of the chamber to a maximum radius of curvature at the valve end of the chamber, and a fuel spray nozzle having an outlet at the cylinder end of said channel portion constructed and arranged to spray liquid fuel longitudinally of said chamber and to discharge substantially the main portion of the fuel charge directly upon said exhaust valve.

2. In an internal combustion engine, a cylinder block provided with a cylinder bore and an exhaust valve located at one side of said cylinder bore. a cylinder head having an inlet valve opening directly into the end of said cylinder bore, a compression chamber in said cylinder head having a cylindrical lobe slightly larger in diameter than said exhaust valve and substantially concentric therewith and having a communicating laterally tapered channel of less maximum width than the diameter of said lobe, said channel having a longitudinally;--extending arcuate groove in its roof varying in curvature from a minimum radius of curvature at the cylinder end of the chamber to a maximum radius of curvature at the valve end of the chamber, and a fuel spray nozzle having an outlet at the cylinder end of said channel constructed and arranged to discharge a fuel spray longitudinally of said chamber and having a pattern conforming to the arcuate groove of said channel roof.

GILBERT C. GOODE. CLARENCE W. MILLER. GEORGE R. HARRINGTON. 

